Environmental and regulatory initiatives are requiring ever lower levels of both sulfur and aromatics in distillate fuels. For example, proposed sulfur limits for distillate fuels to be marketed in the European Union for the year 2005 is 50 wppm or less. There are also proposed limits that would require lower levels of total aromatics as well as lower levels of multi-ring aromatics found in distillate fuels and heavier hydrocarbon products. Further, the maximum allowable total aromatics level for CARB (California Air Resources Board) reference diesel and Swedish Class I diesel are 10 and 5 vol. %, respectively. Further, the CARB reference fuels allows no more than 1.4 vol. % polyaromatics (PNAs). Consequently, much work is presently being done in the hydrotreating art because of these proposed regulations.
Still further, with the advent of increased environmental concerns, the performance requirements for lubricating oil basestocks themselves have also increased. For example, the American Petroleum Institute (API) requirements for Group II basestocks include a saturates content of at least 90%, a sulfur content of 0.03 wt. % or less and a viscosity index (VI) between 80 and 120. Currently, there is a trend in the lube oil market to use Group II basestocks instead of Group I basestocks in order to meet the demand for higher quality basestocks that provide for increased fuel economy, reduced emissions, etc. For example, American Petroleum Institute (API) requirements for Group II basestocks include a saturates content of at least 90%, a sulfur content of 0.03 wt. % or less and a viscosity index (VI) between 80 and 120.
Thus, as the environmental and regulatory initiatives to increase, the search for new and different processes, catalysts, and catalyst systems that exhibit improved sulfur and nitrogen removal and aromatics saturation activity is a continuous, ongoing exercise. Therefore, there is a need to provide hydrocarbonaceous products that meet the demand for increased fuel economy, reduced emissions, etc.